State estimated tax calculator for 2026: the safe-harbor amount by state

The short answer Type last year's state tax and your estimate of this year's, pick the state, and the calculator returns the smallest amount that meets the state's safe harbor and splits it across the state's due dates. It covers 37 states with a stated percentage rule; for the rest it shows the state's own sentence. Turn on the federal line to see the Form 1040-ES amounts next to it.

Enter last year's tax and this year's estimate to see the installments.

How the safe harbor works

An underpayment penalty is interest on tax that should have been paid during the year. Every state with an estimated-payment regime publishes an amount that avoids it: pay at least this much through withholding and installments and the penalty does not apply, whatever the final bill. The federal version is the smaller of 90 percent of the current-year tax or 100 percent of the prior-year tax, 110 percent for higher incomes. Most states follow it, but not all. Colorado needs only 70 percent of the current year; Massachusetts and New Jersey 80 percent; Hawaii 60 percent. Maryland and the District of Columbia set the prior-year test at 110 percent for everyone. Mississippi, Arkansas, Pennsylvania and Rhode Island publish no prior-year alternative at all. The calculator applies each state's own figures and shows the sentence they came from.

What the calculator does not do

Frequently asked questions

How are state estimated tax payments calculated?

Most states copy the federal rule: pay, through withholding and four installments, the smaller of a percentage of this year's tax (usually 90 percent) or a percentage of last year's tax (usually 100 percent, rising to 110 percent above an income threshold). The calculator applies each state's own percentages from its instructions, divides by the number of installments, and shows the dates.

What is the safe harbor for estimated taxes?

The amount you can pay in during the year and owe no underpayment penalty even if the final tax turns out higher. Federally it is the smaller of 90 percent of the current-year tax or 100 percent of the prior-year tax, 110 percent if prior-year AGI was over $150,000 ($75,000 married filing separately). States set their own: Colorado uses 70 percent, Massachusetts and New Jersey 80 percent, Hawaii 60 percent, Maryland and DC 110 percent of the prior year for everyone.

Which states do not require estimated payments?

Idaho and Utah do not require them from individuals, though Utah prepayment matters for the extension penalty. Nine states have no individual income tax: Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington and Wyoming.

Why does California show unequal payments?

California weights the installments 30, 40, 0 and 30 percent of the annual amount across the four dates, with nothing due in September. The calculator applies those weights.

Does this calculator include federal estimates?

Yes. Turn on the federal line to see the Form 1040-ES amounts alongside the state amounts, using the 2026 Form 1040-ES rule: the smaller of 90 percent of 2026 tax or 100 percent of 2025 tax (110 percent if 2025 AGI was over $150,000, or $75,000 married filing separately), due April 15, June 15 and September 15, 2026 and January 15, 2027.

Is this tax advice?

No. It applies the published percentages to the numbers you type. Annualized-income methods, farmers' and fishermen's rules, part-year residents and credits are not modeled. Confirm with your accountant.

Every state's rule, with its source

StateCurrent yearPrior yearHigh incomeNo estimates if you owe underSource
Alabama 90% 100% 110% above $150,000 $500 revenue.alabama.govread September 3, 2026
Arizona 90% 100% $1,000 azleg.govread September 3, 2026
Arkansas 90% not stated $1,000 dfa.arkansas.govread September 3, 2026
California 90% 100% 110% above $150,000 $500 ftb.ca.govread September 3, 2026
Colorado 70% 100% 110% above $150,000 $1,000 tax.colorado.govread September 3, 2026
Connecticut 90% 100% $1,000 portal.ct.govread September 3, 2026
Delaware 90% 100% 110% above $150,000 $800 revenuefiles.delaware.govread September 3, 2026
District of Columbia 90% 110% $100 otr.cfo.dc.govread September 3, 2026
Georgia not stated not stated $1,000 dor.georgia.govread September 3, 2026
Hawaii 60% 100% $500 files.hawaii.govread September 3, 2026
Idaho not stated not stated tax.idaho.govread September 3, 2026
Illinois 90% 100% $1,000 tax.illinois.govread September 3, 2026
Indiana 90% 100% 110% above $150,000 $1,000 in.govread September 3, 2026
Iowa 90% 100% 110% above $150,000 $1,000 revenue.iowa.govread September 3, 2026
Kansas 90% 100% $500 ksrevenue.govread September 3, 2026
Kentucky 90% 100% 110% above $150,000 $500 revenue.ky.govread September 3, 2026
Louisiana 90% 100% $1,000 legis.la.govread September 3, 2026
Maine 90% 100% $1,000 maine.govread September 3, 2026
Maryland 90% 110% $500 marylandcomptroller.govread September 3, 2026
Massachusetts 80% 100% $400 mass.govread September 3, 2026
Michigan 90% 100% 110% above $150,000 $500 michigan.govread September 3, 2026
Minnesota 90% 100% 110% above $150,000 $500 revenue.state.mn.usread September 3, 2026
Mississippi 80% not stated $200 dor.ms.govread September 3, 2026
Missouri 90% 100% $100 dor.mo.govread September 3, 2026
Montana 90% 100% $500 revenuefiles.mt.govread September 3, 2026
Nebraska 90% 100% 110% above $150,000 $500 revenue.nebraska.govread September 3, 2026
New Jersey 80% 100% $400 nj.govread September 3, 2026
New Mexico 90% 100% $1,000 tax.newmexico.govread September 3, 2026
New York 90% 100% 110% above $150,000 $300 tax.ny.govread September 3, 2026
North Carolina not stated not stated $1,000 ncdor.govread September 3, 2026
North Dakota 90% 100% $1,000 tax.nd.govread September 3, 2026
Ohio not stated not stated $500 tax.ohio.govread September 3, 2026
Oklahoma 70% 100% $500 oklahoma.govread September 3, 2026
Oregon 90% 100% $1,000 oregon.govread September 3, 2026
Pennsylvania 90% not stated $430 pa.govread September 3, 2026
Rhode Island 80% not stated $250 webserver.rilegislature.govread September 3, 2026
South Carolina 90% 100% 110% above $150,000 $100 dor.sc.govread September 3, 2026
Utah not stated not stated incometax.utah.govread September 3, 2026
Vermont 90% 100% $500 tax.vermont.govread September 3, 2026
Virginia 90% 100% $1,000 tax.virginia.govread September 3, 2026
West Virginia 90% 100% $600 tax.wv.govread September 3, 2026
Wisconsin 90% 100% $500 revenue.wi.govread September 3, 2026

Sources

General information, not tax advice. The calculator applies published percentages to your inputs and ignores credits, annualization and residency rules. Confirm with your accountant before paying.